We have used neuroimaging techniques in patients with temporal lobe epilepsy to perform non-invasive evaluation of functional cortex. This information is crucial for surgical planning in patients with intractable epilepsy. Both positron emission tomography and functional magnetic resonance imaging can be used to map langauge and memory function. Our studies in both normal volunteers and patients with uncontrolled seizures have shown that imaging evaluation compares well with more invasive procdures such as electrostimulation mapping and the intracarotid sodium amytal test. More recently, we used transcranial magnetic stimulation (TMS) to map memory function and language localization in patients with left hemisphere speech dominance. Left frontal stimulation led to speech arrest, and left temporal to picture naming errors. Both right and left frontal stimulation disrupted memory for pictures; left posterior temporal TMS disrupted naming during encoding but not memory. TMS is a useful tool for investigation of language and memory organization. Our current studies are directed toward evaluating whether the presence of a seizure focus, particulalry one developing in childhood, leads to functional brain reorganization.